SpringMVC里面有许多HandlerMapping，对这块还不太了解，所以决定了解一下这些东东的作用。
先来看第一个：org.springframework.web.servlet.handler.SimpleUrlHandlerMapping
官方的api文档解释如下：
Implementation of the org.springframework.web.servlet.HandlerMapping interface to map from URLs to request handler beans.
简单来说，就是实现了HandlerMapping接口，处理url到bean的映射，比如下面这些映射：
/welcome.html=ticketController
/show.html=ticketController
一个url对应一个bean，但是这个bean有个要求，就是实现Controller接口，下面看一个实例。
1.Controller如下：
1 package com.springmvc.demo.controller;
2
3 import javax.servlet.http.HttpServletRequest;
4 import javax.servlet.http.HttpServletResponse;
5
6 import org.springframework.stereotype.Controller;
7 import org.springframework.web.servlet.ModelAndView;
8 import org.springframework.web.servlet.mvc.AbstractController;
9
10 @Controller
11 public class SimpleController extends AbstractController {
12
13 @Override
14 protected ModelAndView handleRequestInternal(HttpServletRequest request,
15 HttpServletResponse response) throws Exception {
16 System.out.println("SimpleController...");
17 System.out.println(request.getParameter("username"));
18 ModelAndView mv = new ModelAndView("simpleController");
19 mv.addObject("msg", "hello,SimpleController");
20 return mv;
21 }
22
23 }
2.为了对比，再建一个Controller，这个没有实现Controller接口，而是使用注解：
1 package com.springmvc.demo.controller;
2
3 import javax.servlet.http.HttpSession;
4
5 import org.springframework.stereotype.Controller;
6 import org.springframework.ui.ModelMap;
7 import org.springframework.validation.BindingResult;
8 import org.springframework.web.bind.annotation.ModelAttribute;
9 import org.springframework.web.bind.annotation.RequestMapping;
10 import org.springframework.web.bind.annotation.RequestParam;
11 import org.springframework.web.servlet.ModelAndView;
12
13 import com.springmvc.demo.model.User;
14
15 @Controller
16 @RequestMapping("/user")
17 public class UserController {
18
19 @RequestMapping("/add")
20 public ModelAndView addUser(@RequestParam String username,
21 @RequestParam String password,
22 @RequestParam int id,
23 HttpSession session){
24
25 ModelAndView mv = new ModelAndView();
26 mv.setViewName("hello");
27 User u = new User();
28 u.setUsername(username);
29 u.setPassword(password);
30 u.setId(id);
31 mv.addObject("user", u);
32 session.setAttribute("user", u);
33
34 return mv;
35 }
36
37 /*@ModelAttribute
38 public User getUser(){
39 User u = new User();
40 u.setId(12);
41 return u;
42 }*/
43
44 @RequestMapping("/preAddUser")
45 public String preAddUser(ModelMap map){
46 User u = new User();
47 map.addAttribute("user", u);
48 return "index";
49 }
50
51 @RequestMapping("/addUser")
52 public String addUser2(@ModelAttribute("user") User user,BindingResult result,ModelMap map){
53 if(user.getUsername().equals("yang")){
54 map.addAttribute("user", user);
55 return "index";
56 }
57 /*ModelAndView mv = new ModelAndView();
58
59 mv.setViewName("hello");
60 mv.addObject("user", user);*/
61
62 return "hello";
63 }
64
65 }
3.页面simpleController.jsp：
1 <!DOCTYPE html> 2 <html> 3 <body> 4 5 <form action="/springmvc/simpleController" method="post"> 6 <input type="text" name="username"/> 7 <input type="text" name="password"/> 8 <!-- <input type="text" name="id"/> --> 9 <input type="submit" value="submit" /> 10 </form> 11 </body> 12 </html>
4.MVC配置文件：
1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" 4 xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" 5 xsi:schemaLocation=" 6 http://www.springframework.org/schema/beans 7 http://www.springframework.org/schema/beans/spring-beans.xsd 8 http://www.springframework.org/schema/context 9 http://www.springframework.org/schema/context/spring-context.xsd 10 http://www.springframework.org/schema/mvc 11 http://www.springframework.org/schema/mvc/spring-mvc.xsd"> 12 13 <context:component-scan base-package="com.springmvc.demo.controller" /> 14 15 <!-- <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping" /> 16 <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter" /> --> 17 <!-- <mvc:default-servlet-handler/> --> 18 <!-- <mvc:annotation-driven /> --> 19 <!-- <mvc:resources location="/resource/images/" mapping="/images/**" /> --> 20 <bean id="simpleController" class="com.springmvc.demo.controller.SimpleController"></bean> 21 22 <bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> 23 24 <property name="urlMap"> 25 <map> 26 <entry key="/simpleController" value-ref="simpleController" /> 27 </map> 28 </property> 29 </bean> 30 31 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> 32 <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> 33 <property name="prefix" value="/" /> 34 <property name="suffix" value=".jsp" /> 35 </bean> 36 37 38 </beans>
测试一：
访问simpleController.jsp，点击提交，访问正常
测试二：
访问/user/add，显示404
总结：
SimpleUrlHandlerMapping只支持实现了Controller接口的bean，且还需要在其属性里进行url路径-->bean的映射，不支持@RequestMapping注解，所以这个SimpleUrlHandlerMapping功能很有限
注：还可以使用mappings属性进行配置，效果是一样的：
<!-- mappings是一Properties对象 --><property name="mappings">
<props>
<prop key="/simpleController">simpleController</prop>
</props>
</property>
时间： 2024-11-03 05:43:24